for geometry, that they had accumulated a store of memories, unconsciously, that made Euclid an easy book comparatively for them, but that our children do not gather such memories of space and place always in the open, so they have less instinct for geometry, and are not prepared to learn it out of books.) Many people are not yet well furnished with brain chambers for various kinds of memory. For example, the place for word-memories must be still small in the labourer's brain. He does not need many words. Still he needs more now than formerly, and his brain is modified in consequence. Then his fingers were once too stiff to hold a pen, but now he can write, however stiffly or slowly. In short, many doors which were fast locked before are now being opened. There is probably no brain that is equally well developed in every part. In every one there are empty and shrunken chambers, and even gaps or rooms entirely missing, and sometimes a room may be crowded out altogether, as happens in the case of people who specialize too much or too early.
But, as we have seen, the middle brain is not a mere granary—or place where needful things are stored. It is a laboratory—the place in which at last what was mere vibration of air or ether is
